JP2004503126A - Power control algorithm for packet data based on queue / channel utilization - Google Patents

Abstract

Disclosed are systems and methods for channel quality improvement in packet data wireless networks. In each cell of the wireless network, packet data is measured based on channel utilization and / or packet queue measurements. The power control algorithm uses the packet data load to determine a common or equal, broadcast or transmit power level for the cell's channel. The common broadcast and transmit power may be later adjusted on an individual channel basis for channels that fall outside the predefined quality window.

Description

[0001]
Priority claim
This patent application was filed with the United States Patent and Trademark Office on July 5, 2000, and entitled "Power Control Algorithm for Packet Data Based on Queue / Power Control Algorithm for Packet Data Based on Queue / Channel Utilization." No. 60 / 215,954, entitled "Channel Utilization", which is incorporated herein by reference.
[0002]
Background of the Invention
TECHNICAL FIELD OF THE INVENTION
The present invention relates to improving channel quality in packet mobile wireless networks, and more particularly, to a method and system therefor using a power control algorithm.
[0003]
Background of related technology
Power control has traditionally been used in mobile wireless networks as a way to improve channel quality between mobile terminals and the network. For example, the transmit power is increased to improve the channel to interference ratio (C / I) of the channel, thereby improving the data rate and throughput of the channel. The transmit power is also reduced to reduce the channel's interference with other channels.
[0004]
Examples of such power control are found in circuit-switched mobile radio networks such as the Pan-European Digital Mobile Telephone System (GSM), where the transmit power is adjusted on an individual channel basis. For example, US Patent No. 5,574,982 to Magnus Almgren, Hakan Andersson, and Kenneth Wallstedt, entitled "Power Control in a Cellular Cell Cell System. ) ". This adjustment includes received signal strength indication (RSSI), C / I, bit error rate (BER), bit error probability (BEP), energy per bit due to noise (Eb / No), frame erasure rate (FER), etc. Made according to any number of known radio link quality measurements.
[0005]
Power control for packet-switched mobile radio networks may be found in the GSM standard, GSM 05.08 (version 8.5.0), which includes a proposal for power control in the Advanced General Packet Radio System (EGPRS). Absent.
[0006]
Similarly, control of transmission power is a central function of systems using code division multiple access (CDMA). Because all channels must share the same set of frequencies. See the UMTS standard 3GPP TS 25.214 (version 3.5.0), which provides power control specifications for the Universal Mobile Telecommunication System (UMTS), which is a CDMA system.
[0007]
However, it is generally difficult to measure radio link quality with sufficiently high accuracy in currently available mobile radio networks. Such difficulties, in part, require that quality measurements be made remotely by the mobile terminal and then sent to the mobile wireless network or otherwise reported and processed. In that way, the possibility of reporting an error arises because it is opened. The difficulty of measurement is greater for packet data transmissions with short packets and intermediate arrival times of long packets. This is due to the fact that during times of no transmission, the measurement accuracy is lower or the signaling overhead for the measurement is higher.
[0008]
Furthermore, radio link quality as affected by quality measurements such as C / I may not be a very good indicator of channel quality for mobile wireless networks using packet data. For example, C / I may not be able to accurately reflect packet delays due to queuing that reduces the channel data rate and therefore degrades channel quality. Computer simulations of such packet data mobile radio networks have shown, for example, that users with the worst channel quality do not have very low radio link quality.
[0009]
It is therefore desirable to be able to improve channel quality in packet data mobile radio networks and to do so with measurements that more accurately reflect the actual channel quality in such packet data networks.
[0010]
Summary of the Invention
Some embodiments of the present invention provide methods and systems for improving channel quality in packet data wireless networks. In a cell of a wireless network, packet data is measured based on channel utilization and / or packet queue measurements. The power control algorithm uses the packet data load to determine a common or equal broadcast or transmit power level for multiple channels in the cell. The common broadcast or transmit power may later be adjusted on an individual channel basis for channels that fall outside the predefined quality window.
[0011]
In general, in one aspect, the invention relates to a method for controlling transmission power in a cell of a packet data mobile radio network. The method includes measuring a packet data load in a cell, determining a common transmission power based on the packet data load, and applying the common transmission power to multiple channels of the cell. I have.
[0012]
In general, in another aspect, the invention is directed to a system for controlling transmission power in a cell of a packet data mobile wireless network. The system includes a base radio station, a channel scheduler at the base radio station configured to measure packet data load in a cell, and a power control unit coupled to the channel scheduler and having a power control algorithm. are doing. The power control algorithm is configured to determine a common transmission power based on a packet data load, and the power control unit is configured to apply the common transmission power to a plurality of channels of the cell.
[0013]
In general, in yet another aspect, the invention relates to a method of celling transmit power in a cell of a packet data mobile radio network. The method measures the load of packet data in the cell based on a predetermined one of channel utilization and packet queue measurement, determines a common transmission power based on the load of packet data, The common transmission power is applied to a plurality of channels of a cell. The radio link quality is measured for multiple channels, and the common transmission power is determined for the radio link outside the quality window defined based on a predetermined one of the channel data rate and the carrier-to-interference ratio. Adjusted for channels with quality level.
[0014]
Advantages of the present invention include packet data mobile wireless networks, local power control algorithms at the base station, and improved channel quality and capabilities in quality measurements directly available at the base station. . Other advantages of the invention will be apparent from the following description and from the claims.
[0015]
A more complete understanding of the method and system of the present invention will be obtained by reference to the detailed description in conjunction with the accompanying drawings.
[0016]
Detailed description of exemplary embodiments
Next, typical embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same reference numerals in the drawings denote the same constituent elements in the following drawings.
[0017]
As described above, some embodiments of the present invention provide methods and systems for improving channel quality in a packet data mobile wireless network. Such networks may include a general packet radio system (GPRS), an improved general packet radio system (EGPRS), or other packet switched networks.
[0018]
In general, packet-switched networks differ from traditional circuit-switched mobile radio networks because circuit-switched networks typically have a fixed number of channels for each assigned radio frequency. The term "channel" as used herein refers to a radio frequency link between a mobile terminal and a mobile radio network. For example, in GSM, each channel typically occupies one time slot of the assigned radio frequency. Thus, the number of mobile terminals using a given radio frequency in a circuit-switched network is limited to the number of available time slots per radio frequency (usually eight time slots).
[0019]
In contrast, packet-switched networks have flexibility in the number of channels per assigned radio frequency. This is because one time slot can carry two or more different channels because of the recombining nature of packet data. For example, in EGPRS, each channel can occupy only a portion of a time slot up to a number of time slots, depending on the total number of time slots available at each radio frequency. Thus, the number of mobile terminals using a given radio frequency at any given time in a packet switched network may exceed the number of available time slots. Thus, the packet switching network has the additional parameters available there and tunes the channel quality, ie the number of channels and the amount of channels.
[0020]
FIG. 1 illustrates relevant portions of a typical packet data mobile wireless network 100. The packet data mobile wireless network 100 includes a plurality of cells 102, each cell 102 having a plurality of radio frequencies assigned thereto for use therein. Radio frequencies are typically allocated to cells 102 by the packet data mobile radio network 100 according to a predefined frequency allocation plan. Each cell 102 further has at least one base radio station 104 that transmits / receives mobile calls from / to a plurality of mobile terminals (not shown) depending on the assigned radio frequency. . Base station controller 106 controls the operation of at least one base radio station 104 (eg, handover, channel assignment, etc.). The base station controller 106 is then controlled by a packet data core network 108 that includes, for example, a serving GPRS support node (SGSN) and a gateway GPRS support node (GGSN). The packet data core network 108 routes mobile calls between the packet data mobile wireless network 100 and other telephone networks and / or data communication networks. Such other telephone networks and / or data communication networks 110 may include, for example, a global packet data network 110 such as the Internet.
[0021]
FIG. 2 illustrates a base wireless station 104 according to some embodiments of the present invention. Base radio station 104 has a number of functional components, including cell power control unit 200 and cell channel scheduler 202. In operation, a plurality of packets 204 from the packet data core network 108 are received at the base station 104, where they are temporarily stored. Thereafter, the received packet 204 is processed by functional components of the base station 104, including the cell power control unit 200 and the cell channel scheduler 202. The processed packet 204 is then transmitted to one or more mobile terminals 208a-208c via one or more transceiver units 206a-206c. Similarly, packets received from mobile terminals 208a-208c are received by transceiver units 206a-206c and subsequently processed by base station 104 and forwarded to packet data core network 108.
[0022]
Although the appropriate broadcast or transmit power level may be used individually for each channel, in some embodiments the packet 204 is equal or common for all or substantially all channels in the cell. It is broadcast or transmitted to the mobile terminals 208a to 208c using the power level. Transmitting at a common power level for all or substantially all channels has the effect of improving channel quality throughout the cell. This effect is described, for example, by Arn Simonsson, Magnus Almgren, and Magnus Thurjell, “A Power Control and Scheduling Concept (A Power Control and Scheduling Concept). In the article entitled " The paper states that approaching the optimal cell data rate and / or throughput is achieved by using equal or common power levels in connection with adjusting channel quality. I have. The paper further states that channel quality can be either channel allocation (i.e., changing the number of time slots available for a given mobile terminal) or channel scheduling (i.e., 1 available for a given mobile terminal). (Changing a part of one time slot) or a combination of both.
[0023]
In the above embodiments, all or substantially all of the channels are broadcast or transmitted using equal or common power levels, but in other embodiments, less than all channels are identified. May be broadcast or transmitted using equal or common power levels, depending on the requirements of the packet data wireless network. For example, equal or common power levels may be applied to channel groups or user groups. User groups or channel groups may be defined, for example, based on their Quality of Service (QOS) requirements or other similar criteria. By transmitting at an equal or common power level for such a service group, more radiated interference is produced as compared to transmitting at an individual power level to the individual mobile terminals of the service group. Can be reduced. This effect is also described in the above-mentioned article, where a smaller radiated co-channel interferer is achieved while the scheduled channel quality for each mobile terminal is reduced. It is described that channel quality can be maintained using equal or common power levels in connection with the adjustment.
[0024]
FIG. 3 illustrates a cell power control unit 200 according to some embodiments of the present invention. The cell power control unit 200 has a number of functional components, including a channel power controller 300 therein. The channel power controller 300 mainly functions to control broadcast or transmission power of each channel in the cell. Specifically, the channel power controller 300 controls the broadcast or transmission power for each of the plurality of time slots 0 to 7 at the radio frequencies 304a to 304c assigned to the cell. Techniques for controlling the broadcast or transmit power of a time slot (and therefore any channel there) are known to those skilled in the art and will not be described here. It should be noted, however, that power control is attempted to avoid "party" effects that may occur, as described in the aforementioned US Pat. No. 5,574,982, incorporated herein by reference. Attention should be paid at times.
[0025]
In some embodiments, cell power control unit 200 performs its function using a power control algorithm 302 (dashed line) configured to establish equal or common power levels for channels in the cell. The power control algorithm 302 determines this equal or common power level, for example, based on the measured packet data load for the cell or a portion of the cell, or other similar cell load measurements. For example, in some embodiments, if the packet data load for a cell or a portion of that cell is at a particular high or maximum level, then the common or equal power level generated by power control algorithm 302 will be at a particular level. May be high or maximum power level. Alternatively, if the packet data load for a cell or a portion of that cell is at a particular low or lowest level, then the common or equal power level generated by the power control algorithm 302 may be at a particular low or lowest power level. might exist. In general, the power control algorithm 302 determines whether the optimal data rate and / or throughput is close to the packet data load such that at least one of the optimal data rate and the throughput is achieved for the cell or a portion of the cell. Determine the power level.
[0026]
After such an equal or common power level is determined, the channel power controller 300 may broadcast or broadcast for some, all, or substantially all channels in the cell according to the recently determined common power level. Adjust the transmission power level. Channel power controller 300 makes these adjustments by adjusting the power levels for each of time slots 0-7 at radio frequencies 304a-304c assigned to the cell.
[0027]
In some embodiments, the measured packet data load in a cell may be based on either the channel utilization of the cell, one or more packet queue measurements, or a combination of both. As used herein, the term "channel utilization" refers to the degree or degree to which a channel in a cell uses an assigned radio frequency. For example, full channel utilization means that 100% of all time slots of the assigned radio frequency are currently in use. In some embodiments, the immediate value of the packet data load may be used by power control algorithm 302. In other embodiments, a statistically generated value of the packet data load (eg, a temporal average) may be used instead. In yet another embodiment, the value of the packet data load may be a filter or weighted value based on one or more criteria according to a predetermined weighting scheme. In any case, thereafter, the packet data load is factored into the power control algorithm 302 and is used to create an equal or common power level for the cell's channel.
[0028]
In some embodiments, channel utilization and packet queue measurements used to determine packet data load may be obtained by monitoring the operation of cell channel scheduler 202. FIG. 4 illustrates a cell channel scheduler 202 according to these embodiments of the present invention. The cell channel scheduler 202 has a number of functional components including a packet queue 400 and a packet queue controller 402. Packet queue controller 402 controls channel scheduling and assignment of packets 204 stored in packet queue 400. In contrast, packet queue 400 serves as a temporary repository for packets 204 received by base station 104 until the packets are placed by queue controller 402.
[0029]
As described above, in the packet data mobile radio network 100, the number of channels per allocated radio frequency 404 is flexible. Thus, each of the assigned time slots 0-7 of the radio frequency 404 may be shared by one or more mobile terminals, as assigned and scheduled by the packet queue controller 402, or A time slot may be used by one mobile terminal. For example, the packet queue controller 402 may allocate and schedule packets for mobile terminals A to K as follows. That is, packets transmitted to mobile terminals A and B sharing time slot 0 equally, packets transmitted exclusively to mobile terminal C occupying time slot 1 exclusively, and time slot 2 shared in the same manner. Packets transmitted to mobile terminals D, E, and F, packets transmitted to mobile terminal G that exclusively occupies both time slots 3 and 4, and time slot 5 of that time slot. The mobile terminal H and mobile terminal I, which use most of them, are unbalanced but shared, and packets transmitted to these H and I, the mobile terminal J partially occupy the time slot 6 and the remaining The part is left unused, and there is a packet transmitted to this J, and finally, a packet transmitted to the mobile terminal K which exclusively occupies the time slot.
[0030]
It should be noted that in some embodiments, each assigned radio frequency 404 has eight time slots 0-7, but in other embodiments, a different number of time slots may be used for specific specifications of the packet data mobile radio network 100. Depending on the case, it may be used.
[0031]
The aforementioned channel utilization (ie, channel assignment and scheduling) may later be used as a basis to determine the packet data load on a cell or a portion of that cell. Such channel utilization information is obtained by the cell channel scheduler 202, for example, by monitoring the queue controller 402 according to known techniques. The cell channel scheduler 202 may thereafter determine the packet data load, or may simply pass the channel utilization information to the cell power control unit 200 to determine the packet data load. This packet data load information is incorporated as a factor of the power control algorithm 302 of the cell power control unit 200. Power control algorithm 302 then determines an equal or common power level for some, all, or substantially all channels within the cell, as described above.
[0032]
In some embodiments, instead of channel utilization information, one or more measurements of packets in packet queue 400 may be used as a basis for determining packet data load in a cell or a portion of that cell. good. Such packet queue measurements may include, for example, the queue length of some, all, or substantially all queues, the maximum queue length of any one queue, some, all, or substantially all queues. Average or immediate queue length changes (ie, increase / decrease in queue length), distribution of packet size in some, all, or substantially all queues, maximum packet size in any queue, and other similarities May be included. As in the case of channel utilization information, packet queue measurements may also be obtained by the cell channel scheduler 202 through monitoring of the packet queue 400 according to known techniques. The cell channel scheduler 202 may thereafter determine the packet data load, or may pass the measurement to the cell power control unit 200 to make the load determination.
[0033]
In some embodiments, a quality window may be performed. Within that window, the common cell power results in an appropriate data rate and / or throughput for the cell or a portion of the cell. FIG. 5 illustrates graphs of data rate versus C / I for two representative types of data modulation, GMSK (Gaussian minimum shift keying) and 8-PSK (8 phase shift keying). Here, GMSK and 8-PSK may be used to define a representative quality window. The horizontal axis of the graph represents C / I in units of dB, and C / I may reflect broadcast or transmission power. On the other hand, the vertical axis represents the data rate in units of kbps / time slot. Note that the graph shown in FIG. 5 is based only on computer simulation data for the GPRS network, and not based on actual data.
[0034]
As shown, above a certain point, little or no gain in channel data rate is obtained by increasing C / I (eg, by increasing broadcast or transmission power). Absent. For GMSK modulation, the point is found at a data rate of about 20 kbps / time slot, and for 8-PSK modulation, the point is found at a data rate of about 60 kbps / time slot. Similarly, below a certain point, it is better to reduce the channel data rate (eg, reduce the number of time slots per channel) than to reduce broadcast or transmission power. In this regard, the data rate should be around 8 kbps / time slot to minimize transmission power consumption. This point may be located at a data rate of 14 kbps / time slot to minimize interference to other channels. (See the article entitled "A Power Control and Scheduling Concept for EGPRS" above.) Thus, for GMSK, the lower and upper bounds of the quality window are about Preferably, it is 7 to 20 kbps / time slot, and for 8-PSK, it is about 14 to 60 kbps / time slot.
[0035]
The data rate is described in kbps / time slot. Therefore, if the data rate is, for example, 7 kbps / time slot, for example, a channel occupying two time slots has a data rate of 14 kbps for all channels, but a channel occupying half of one time slot is a channel. The data rate is 3.5 kbps.
[0036]
The aforementioned data points are the upper and lower quality windows that may be factored into the power control algorithm 302 for determining equal or common power levels for some, all, or substantially all channels of the cell. It is good to be realized as. For example, when determining the data rate for some, all, or substantially all channels of a cell, if any channel has a data rate that falls outside its quality window, then the power control The algorithm 302 adjusts (eg, increases or decreases) the broadcast or transmit power to the affected mobile terminals relative to a common power level, bringing the channel data rate within the window. The individual channel data rates may be determined by the base station 104, for example, according to known techniques.
[0037]
In another embodiment, instead of the channel data rate, the quality window may be implemented based on one or more other known channel quality measurement methods. For example, referring again to FIG. 5, the upper and lower limits of the quality window may be based on C / I. Under such a configuration, the range from the upper to lower limits of the quality window is found around 7-25 dB for GMSK and around 7-35 dB for 8-PSK. Thus, if the C / I for an individual channel is determined to be outside, or transition outside, its quality window (eg, by base radio station 104), then power control algorithm 302 The broadcast or transmission power level to the affected mobile terminal is adjusted relative to the common power level to bring its C / I back within the window.
[0038]
In yet another embodiment, the broadcast or transmission power level for a given channel may be adjusted by a predefined offset based on a quality of service profile for the user. For example, a user requiring a constant channel data rate or a constant C / I may have a predefined offset applied relatively to a common cell power level for packets transmitted to his particular mobile terminal. And the required service quality may be guaranteed.
[0039]
The foregoing description has focused on embodiments of the present invention involving a downlink channel or a channel that carries packets transmitted to mobile terminals. However, the invention is not limited thereby, and in some embodiments, the teachings herein also apply to uplink channels. In other words, a power control algorithm functionally similar to power control algorithm 302 may be implemented at base radio station 104 for power control of the mobile terminal. In that case, the packet queue measurement information may be limited, but the channel utilization information is certainly available to be used in the mobile terminal power control algorithm.
[0040]
FIG. 6 illustrates a method 600 of power control according to an exemplary embodiment of the present invention. Method 600 is used to improve the channel quality of a cell in a cell of a packet data mobile wireless network by achieving an equal or common power level for some, all, or substantially all channels of the cell. Can be In step 601, the packet data load for a cell or a portion of that cell is measured using either channel utilization, packet queue measurements, or a combination of both. The power control algorithm determines, at step 602, an equal or common broadcast or transmit power level for some, all, or substantially all channels of the cell based on the packet data load. Such packet data load may be an immediate packet data load or may be weighted depending on the specific requirements of the packet data mobile radio network. In step 603, equal or common power levels are achieved for some, all, or substantially all channels of the cell. At step 604, a determination is made as to whether any channels of the cell are outside the quality window. The quality window may be based on channel quality measurements, such as channel data rate, C / I, or another similar quality measurement. If the determination in step 604 is affirmative (Yes), then in step 605, the broadcast or transmission power for the affected mobile terminal is adjusted relative to the common cell power, and Return to step 604. On the other hand, if the judgment is negative (No), the process returns to the first step 601.
[0041]
While the invention has been described with reference to various embodiments, those skilled in the art will recognize that changes may be made to these embodiments without departing from the principles and teachings of the invention. Will. The scope of the present invention is defined by the appended claims.
[Brief description of the drawings]
FIG.
2 illustrates relevant parts of an exemplary mobile wireless network.
FIG. 2
Fig. 3 illustrates a base station according to some embodiments of the invention.
FIG. 3
FIG. 4 illustrates a cell power control unit according to some embodiments of the invention.
FIG. 4
Fig. 4 illustrates a cell channel scheduler according to some embodiments of the invention.
FIG. 5
Fig. 4 illustrates a graph of time slot data rate versus C / I.
FIG. 6
4 illustrates a method according to some embodiments of the invention.

Claims (43)

A method for controlling transmission power in a cell of a packet data mobile radio network, comprising:
Measuring the load of packet data in the cell;
Determining a common transmission power based on the load of the packet data,
Applying the common transmit power to a plurality of channels of the cell. The method of claim 1, wherein the plurality of channels comprises substantially all of the cells. The method of claim 1, wherein the plurality of channels comprises a group of channels defined based on quality of service requirements therefrom. The method of claim 1, wherein the plurality of channels comprises including a group of users defined based on quality of service requirements therefrom. The method of claim 1, wherein the plurality of channels include a downlink channel. The method of claim 1, wherein the plurality of channels include uplink channels. The method of claim 1, wherein the load of the packet data is weighted according to one or more predetermined criteria. The method of claim 1, wherein the common transmit power is adjusted with a predefined offset based on a quality of service profile of an individual user. The method of claim 1, wherein the packet data load is based on channel utilization. The method of claim 1, wherein the load of the packet data has been statistically derived over a predefined time. The method of claim 1, wherein the packet data load is based on packet queue measurements. The method of claim 11, wherein the packet queue measurement includes a total queue length. The method of claim 11, wherein the packet queue measurement includes a longest queue. The method of claim 11, wherein the packet queue measurement includes a change in queue length. The method of claim 11, wherein the packet queue measurement includes a distribution of packet lengths. The method of claim 11, wherein the packet queue measurement includes a longest packet. 2. The method of claim 1, further comprising measuring radio link quality for the plurality of channels and adjusting the common transmission power for channels having a radio link quality level outside a predefined quality window. The method described in. The method of claim 17, wherein the radio link quality comprises a channel data rate. The method of claim 17, wherein the radio link quality comprises a carrier to interference ratio. The quality window is defined by a channel data rate from an upper limit to a lower limit of about 7 to 20 kbps / time slot for GMSK and about 14 to 60 kbps / time slot for 8-PSK. 18. The method according to 17. 18. The quality window of claim 17, wherein the quality window is defined by an upper to lower carrier to interference ratio of about 7 to 25 dB for GMSK and about 7 to 35 dB for 8-PSK. Method. A system for controlling transmission power in a cell of a packet data mobile radio network, comprising:
A base radio station,
A channel scheduler at the base radio station configured to measure packet data load in the cell;
A power control unit connected to the channel scheduler and having a power control algorithm,
The power control algorithm is configured to determine a common transmission power based on the packet data load,
The system, wherein the power control unit is configured to apply the common transmit power to a plurality of channels of the cell. 23. The system of claim 22, wherein the plurality of channels include substantially all of the cells. 23. The system of claim 22, wherein the plurality of channels include a group of channels defined based on quality of service requirements therefrom. 23. The system of claim 22, wherein the plurality of channels includes including a group of users defined based on quality of service requirements therefrom. The system of claim 22, wherein the plurality of channels include a downlink channel. The system of claim 22, wherein the plurality of channels include an uplink channel. 23. The system of claim 22, wherein the load of the packet data is weighted according to one or more predetermined criteria. 23. The system of claim 22, wherein the power control program is further configured to adjust the common transmit power at a predefined offset based on an individual user's quality of service profile. The system of claim 22, wherein the channel scheduler measures the packet data load based on channel utilization. 23. The system of claim 22, wherein the load of the packet data has been statistically derived over a predefined period of time. 23. The system of claim 22, wherein the channel scheduler measures a load of the packet data based on a packet queue measurement. 33. The system of claim 32, wherein the packet queue measurement includes a total queue length. The system of claim 32, wherein the packet queue measurement includes a longest queue. The system of claim 32, wherein the packet queue measurement includes a change in queue length. The system of claim 32, wherein the packet queue measurement includes a distribution of packet lengths. The system of claim 32, wherein the packet queue measurement includes a longest packet. The base radio station is configured to measure radio link quality for the plurality of channels,
23. The system of claim 22, wherein the power control algorithm is further configured to adjust the common transmit power for a channel having a radio link quality level that is outside a predefined quality window. The system of claim 38, wherein the radio link quality comprises a channel data rate. The system of claim 38, wherein the radio link quality comprises a carrier-to-interference ratio. The quality window is defined by a channel data rate from an upper limit to a lower limit of about 7 to 20 kbps / time slot for GMSK and about 14 to 60 kbps / time slot for 8-PSK. 38. The system of claim 38. 39. The quality window of claim 38, wherein the quality window is defined by an upper to lower carrier-to-interference ratio of about 7 to 25 dB for GMSK and about 7 to 35 dB for 8-PSK. system. A method for controlling transmission power in a cell of a packet data mobile radio network, comprising:
Measuring the packet data load in the cell based on a predetermined one of channel utilization and packet queue measurement;
Determining a common transmission power based on the load of the packet data,
Applying the common transmit power to a plurality of channels of the cell;
Measuring radio link quality for the plurality of channels in the cell;
Adjusting the common transmit power for a channel having a radio link quality level outside a quality window defined based on a predetermined one of a channel data rate and a carrier-to-interference ratio. Features method.

Images